Many traditional bitumen extraction processes, such as hot water bitumen extraction, use paraffinic solvent as a carrier liquid to transport extracted bitumen material. As a result, many bitumen extraction facilities are specifically designed for handling and processing compositions of bitumen and paraffinic solvent. For example, pipelines and distillation columns used in some traditional bitumen extraction facilities are tailored for being used with paraffinic solvent having bitumen dissolved therein.
The recent development of new bitumen extraction technologies, such as those described in U.S. Pat. No. 7,909,989, have resulted in the need for bitumen extraction facilities to have the capability to handle other solvents used as carrier mediums for bitumen. For example, the bitumen extracted in the methods described in the '989 patent are dissolved in an aromatic solvent. Accordingly, some modern bitumen extraction facilities must now consider ways in which different solvents having bitumen dissolved therein can be economically and efficiently transported and subjected to downstream processing.
Many of the proposed solutions to this issue are not economic or efficient. For example, one proposed solution is to provide an entirely new infrastructure designed for handling and processing the bitumen-laden aromatic solvent and which is used in conjunction with separate infrastructure designed for handling bitumen-laden paraffinic solvent. Such new and separate systems can include an entirely separate set of pipelines for and separate distillation towers used solely for the separation of aromatic solvent from bitumen. Such a solution is not desirable due to added cost and complexity of such a system. Another proposal has been to operate an existing system in shifts, whereby the existing equipment is alternated between processing the bitumen-laden paraffinic solvent and the bitumen-laden aromatic solvent. Not only does this proposed solution add expense and complexity to the system, but also slows down the overall rate at which the facility can operate. Still another proposal has been to separate the bitumen from the aromatic solvent and mix it with paraffinic solvent so that it can be joined with the bitumen-laden paraffinic solvent produced by the hot water extraction techniques. Such a solution would drastically increase the operating cost of the process and would have a negative impact on the environment due to the CO2 emissions associated with separating the aromatic solvent from the bitumen. Additionally, the asphaltene content in the bitumen separated from the aromatic solvent would subsequently precipitate when added with the paraffinic solvent, which can lead to equipment clogging and other issues.